1. Field of the Invention
The present invention relates generally to surgical devices. More particularly, the invention disclosed herein relates to intramedullary fixation devices.
2. Description of the Related Art
The currently available fixation devices, of which there are many, that are used to treat a long bone fracture or osteotomy are not optimum and therefore need improvement. For example, the currently available fixation devices don't allow stable fixation without an invasive approach that includes opening the adjoining joint and causing irritation of the surrounding soft tissue due to prominence of the profiles of the devices that are attached to the surface of the bones.
Additionally, the prior intramedullary devices provide rotational stability for the treated bones through the use of “locking” screws that are affixed to the bone and require a complex “targeting jig” to correctly align and insert such screws through holes in the intramedullary device. There are also intramedullary devices with deployable elements that are retracted into the intramedullary devices when they are being initially placed into position within the to-be-treated bone or bone segments. These elements diminish the effective thickness of the intramedullary devices in which they are utilized and therefore ultimately weaken the strength of such devices. If the thicknesses or diameters of such devices are increased to accommodate such deployable elements, this can lead to such devices then not being suitable for use in smaller bones whose intramedullary canals are not larger enough to allow for the use of these thicker or larger diameter devices. Finally, such deployable elements have the potential for binding within the intramedullary device and thereby destroying the functionality of such devices.
There are also intramedullary devices that expand or inflate under mechanical pressure in order to affix themselves to the bones that they are being used to treat. These devices require specialized designs, materials of construction and insertion jigs.
Thus, there is a need for the development of improved devices to fixate segments of long bones (e.g., phalanx, metatarsal, metacarpal, radius, ulna, fibula, tibia, femur, humerus, clavicle bone) after an osteotomy or fracture. In certain circumstances, such an improved fixation device might also be used in other types of bones.